Python (PyQt5) 版本的 Qt 标注示例
Python (PyQt5) version of Qt Callout Example
标注示例
From QtCharts package: https://doc.qt.io/qt-5/qtcharts-callout-example.html
This (excellent) example shows how to draw an additional element (a callout) on top of the chart.
问题是是否可以在 python 中实现的某处找到此示例？
我一直在寻找这个移植到 PyQt5 (python) 的示例，但没有找到。所以我自己写了它并想与你分享（只是为了节省你的时间）。它是为 Python 3.8 编写的，但也应该适用于较旧的版本，PyQt 版本是 5.14.1。
与原始的 C++ 实现只有一点点不同。 QGraphicsScene 必须显式设置 - 在 View 构造函数中 class 并且每个新的 Callout 对象都必须显式添加到场景中。坦率地说，我不知道为什么，但我不在乎。 C++ 中完全相同的 Qt 库版本不需要。
import sys
from typing import List
from PyQt5.QtChart import QChart, QLineSeries, QSplineSeries
from PyQt5.QtCore import QPointF, QRect, QRectF, QSizeF, Qt
from PyQt5.QtGui import QColor, QFont, QFontMetrics, QMouseEvent, QPainter, QPainterPath, QResizeEvent
from PyQt5.QtWidgets import QApplication, QGraphicsItem, QGraphicsScene, QGraphicsSceneMouseEvent, \
QGraphicsSimpleTextItem, QGraphicsView, QStyleOptionGraphicsItem, QWidget
class Callout(QGraphicsItem):
def __init__(self, parent: QChart):
super().__init__()
self.m_chart: QChart = parent
self.m_text: str = ''
self.m_anchor: QPointF = QPointF()
self.m_font: QFont = QFont()
self.m_textRect: QRectF = QRectF()
self.m_rect: QRectF = QRectF()
def setText(self, text: str):
self.m_text = text
metrics = QFontMetrics(self.m_font)
self.m_textRect = QRectF(metrics.boundingRect(QRect(0, 0, 150, 150), Qt.AlignLeft, self.m_text))
self.m_textRect.translate(5, 5)
self.prepareGeometryChange()
self.m_rect = QRectF(self.m_textRect.adjusted(-5, -5, 5, 5))
self.updateGeometry()
def updateGeometry(self):
self.prepareGeometryChange()
self.setPos(self.m_chart.mapToPosition(self.m_anchor) + QPointF(10, -50))
def boundingRect(self) -> QRectF:
from_parent = self.mapFromParent(self.m_chart.mapToPosition(self.m_anchor))
anchor = QPointF(from_parent)
rect = QRectF()
rect.setLeft(min(self.m_rect.left(), anchor.x()))
rect.setRight(max(self.m_rect.right(), anchor.x()))
rect.setTop(min(self.m_rect.top(), anchor.y()))
rect.setBottom(max(self.m_rect.bottom(), anchor.y()))
return rect
def paint(self, painter: QPainter, option: QStyleOptionGraphicsItem, widget: QWidget):
path = QPainterPath()
mr = self.m_rect
path.addRoundedRect(mr, 5, 5)
anchor = QPointF(self.mapFromParent(self.m_chart.mapToPosition(self.m_anchor)))
if not mr.contains(anchor):
point1 = QPointF()
point2 = QPointF()
# establish the position of the anchor point in relation to self.m_rect
above = anchor.y() <= mr.top()
above_center = mr.top() < anchor.y() <= mr.center().y()
below_center = mr.center().y() < anchor.y() <= mr.bottom()
below = anchor.y() > mr.bottom()
on_left = anchor.x() <= mr.left()
left_of_center = mr.left() < anchor.x() <= mr.center().x()
right_of_center = mr.center().x() < anchor.x() <= mr.right()
on_right = anchor.x() > mr.right()
# get the nearest self.m_rect corner.
x = (on_right + right_of_center) * mr.width()
y = (below + below_center) * mr.height()
corner_case = (above and on_left) or (above and on_right) or (below and on_left) or (below and on_right)
vertical = abs(anchor.x() - x) > abs(anchor.y() - y)
horizontal = bool(not vertical)
x1 = x + left_of_center * 10 - right_of_center * 20 + corner_case * horizontal * (
on_left * 10 - on_right * 20)
y1 = y + above_center * 10 - below_center * 20 + corner_case * vertical * (above * 10 - below * 20)
point1.setX(x1)
point1.setY(y1)
x2 = x + left_of_center * 20 - right_of_center * 10 + corner_case * horizontal * (
on_left * 20 - on_right * 10)
y2 = y + above_center * 20 - below_center * 10 + corner_case * vertical * (above * 20 - below * 10)
point2.setX(x2)
point2.setY(y2)
path.moveTo(point1)
path.lineTo(anchor)
path.lineTo(point2)
path = path.simplified()
painter.setPen(QColor(30, 30, 30))
painter.setBrush(QColor(255, 255, 255))
painter.drawPath(path)
painter.drawText(self.m_textRect, self.m_text)
def mousePressEvent(self, event: QGraphicsSceneMouseEvent):
event.setAccepted(True)
def mouseMoveEvent(self, event: QGraphicsSceneMouseEvent):
if event.buttons() & Qt.LeftButton:
self.setPos(self.mapToParent(event.pos() - event.buttonDownPos(Qt.LeftButton)))
event.setAccepted(True)
else:
event.setAccepted(False)
class View(QGraphicsView):
def __init__(self, parent=None):
super().__init__(parent)
self.m_callouts: List[Callout] = []
self.setDragMode(QGraphicsView.NoDrag)
self.setVerticalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
self.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
# chart
self.m_chart = QChart(parent)
self.m_chart.setMinimumSize(640, 480)
self.m_chart.setTitle("Hover the line to show callout. Click the line to make it stay")
self.m_chart.legend().hide()
series = QLineSeries()
series.append(1, 3)
series.append(4, 5)
series.append(5, 4.5)
series.append(7, 1)
series.append(11, 2)
self.m_chart.addSeries(series)
series2 = QSplineSeries()
series2.append(1.6, 1.4)
series2.append(2.4, 3.5)
series2.append(3.7, 2.5)
series2.append(7, 4)
series2.append(10, 2)
self.m_chart.addSeries(series2)
self.m_chart.createDefaultAxes()
self.m_chart.setAcceptHoverEvents(True)
self.setRenderHint(QPainter.Antialiasing)
self.setScene(QGraphicsScene())
self.scene().addItem(self.m_chart)
self.m_coordX = QGraphicsSimpleTextItem(self.m_chart)
self.m_coordX.setPos(self.m_chart.size().width() / 2 - 50, self.m_chart.size().height() - 20)
self.m_coordX.setText("X: ")
self.m_coordY = QGraphicsSimpleTextItem(self.m_chart)
self.m_coordY.setPos(self.m_chart.size().width() / 2 + 50, self.m_chart.size().height() - 20)
self.m_coordY.setText("Y: ")
self.m_tooltip = Callout(self.m_chart)
self.scene().addItem(self.m_tooltip)
series.clicked.connect(self.keep_callout)
series.hovered.connect(self.tooltip)
series2.clicked.connect(self.keep_callout)
series2.hovered.connect(self.tooltip)
self.setMouseTracking(True)
def resizeEvent(self, event: QResizeEvent):
if scene := self.scene():
scene.setSceneRect(QRectF(QPointF(0, 0), QSizeF(event.size())))
self.m_chart.resize(QSizeF(event.size()))
self.m_coordX.setPos(self.m_chart.size().width() / 2 - 50, self.m_chart.size().height() - 20)
self.m_coordY.setPos(self.m_chart.size().width() / 2 + 50, self.m_chart.size().height() - 20)
for callout in self.m_callouts:
callout.updateGeometry()
super().resizeEvent(event)
def mouseMoveEvent(self, event: QMouseEvent):
from_chart = self.m_chart.mapToValue(event.pos())
self.m_coordX.setText(f"X: {from_chart.x()}")
self.m_coordX.setText(f"Y: {from_chart.y()}")
super().mouseMoveEvent(event)
def keep_callout(self):
self.m_callouts.append(self.m_tooltip)
self.m_tooltip = Callout(self.m_chart)
self.scene().addItem(self.m_tooltip)
def tooltip(self, point: QPointF, state: bool):
if not self.m_tooltip:
self.m_tooltip = Callout(self.m_chart)
if state:
self.m_tooltip.setText(f"X: {point.x()} \nY: {point.x()} ")
self.m_tooltip.m_anchor = point
self.m_tooltip.setZValue(11)
self.m_tooltip.updateGeometry()
self.m_tooltip.show()
else:
self.m_tooltip.hide()
if __name__ == '__main__':
app = QApplication(sys.argv)
window = View()
window.resize(640, 480)
window.show()
sys.exit(app.exec_())
标注示例
From QtCharts package: https://doc.qt.io/qt-5/qtcharts-callout-example.html
This (excellent) example shows how to draw an additional element (a callout) on top of the chart.
问题是是否可以在 python 中实现的某处找到此示例？
我一直在寻找这个移植到 PyQt5 (python) 的示例，但没有找到。所以我自己写了它并想与你分享（只是为了节省你的时间）。它是为 Python 3.8 编写的，但也应该适用于较旧的版本，PyQt 版本是 5.14.1。
与原始的 C++ 实现只有一点点不同。 QGraphicsScene 必须显式设置 - 在 View 构造函数中 class 并且每个新的 Callout 对象都必须显式添加到场景中。坦率地说，我不知道为什么，但我不在乎。 C++ 中完全相同的 Qt 库版本不需要。
import sys
from typing import List
from PyQt5.QtChart import QChart, QLineSeries, QSplineSeries
from PyQt5.QtCore import QPointF, QRect, QRectF, QSizeF, Qt
from PyQt5.QtGui import QColor, QFont, QFontMetrics, QMouseEvent, QPainter, QPainterPath, QResizeEvent
from PyQt5.QtWidgets import QApplication, QGraphicsItem, QGraphicsScene, QGraphicsSceneMouseEvent, \
QGraphicsSimpleTextItem, QGraphicsView, QStyleOptionGraphicsItem, QWidget
class Callout(QGraphicsItem):
def __init__(self, parent: QChart):
super().__init__()
self.m_chart: QChart = parent
self.m_text: str = ''
self.m_anchor: QPointF = QPointF()
self.m_font: QFont = QFont()
self.m_textRect: QRectF = QRectF()
self.m_rect: QRectF = QRectF()
def setText(self, text: str):
self.m_text = text
metrics = QFontMetrics(self.m_font)
self.m_textRect = QRectF(metrics.boundingRect(QRect(0, 0, 150, 150), Qt.AlignLeft, self.m_text))
self.m_textRect.translate(5, 5)
self.prepareGeometryChange()
self.m_rect = QRectF(self.m_textRect.adjusted(-5, -5, 5, 5))
self.updateGeometry()
def updateGeometry(self):
self.prepareGeometryChange()
self.setPos(self.m_chart.mapToPosition(self.m_anchor) + QPointF(10, -50))
def boundingRect(self) -> QRectF:
from_parent = self.mapFromParent(self.m_chart.mapToPosition(self.m_anchor))
anchor = QPointF(from_parent)
rect = QRectF()
rect.setLeft(min(self.m_rect.left(), anchor.x()))
rect.setRight(max(self.m_rect.right(), anchor.x()))
rect.setTop(min(self.m_rect.top(), anchor.y()))
rect.setBottom(max(self.m_rect.bottom(), anchor.y()))
return rect
def paint(self, painter: QPainter, option: QStyleOptionGraphicsItem, widget: QWidget):
path = QPainterPath()
mr = self.m_rect
path.addRoundedRect(mr, 5, 5)
anchor = QPointF(self.mapFromParent(self.m_chart.mapToPosition(self.m_anchor)))
if not mr.contains(anchor):
point1 = QPointF()
point2 = QPointF()
# establish the position of the anchor point in relation to self.m_rect
above = anchor.y() <= mr.top()
above_center = mr.top() < anchor.y() <= mr.center().y()
below_center = mr.center().y() < anchor.y() <= mr.bottom()
below = anchor.y() > mr.bottom()
on_left = anchor.x() <= mr.left()
left_of_center = mr.left() < anchor.x() <= mr.center().x()
right_of_center = mr.center().x() < anchor.x() <= mr.right()
on_right = anchor.x() > mr.right()
# get the nearest self.m_rect corner.
x = (on_right + right_of_center) * mr.width()
y = (below + below_center) * mr.height()
corner_case = (above and on_left) or (above and on_right) or (below and on_left) or (below and on_right)
vertical = abs(anchor.x() - x) > abs(anchor.y() - y)
horizontal = bool(not vertical)
x1 = x + left_of_center * 10 - right_of_center * 20 + corner_case * horizontal * (
on_left * 10 - on_right * 20)
y1 = y + above_center * 10 - below_center * 20 + corner_case * vertical * (above * 10 - below * 20)
point1.setX(x1)
point1.setY(y1)
x2 = x + left_of_center * 20 - right_of_center * 10 + corner_case * horizontal * (
on_left * 20 - on_right * 10)
y2 = y + above_center * 20 - below_center * 10 + corner_case * vertical * (above * 20 - below * 10)
point2.setX(x2)
point2.setY(y2)
path.moveTo(point1)
path.lineTo(anchor)
path.lineTo(point2)
path = path.simplified()
painter.setPen(QColor(30, 30, 30))
painter.setBrush(QColor(255, 255, 255))
painter.drawPath(path)
painter.drawText(self.m_textRect, self.m_text)
def mousePressEvent(self, event: QGraphicsSceneMouseEvent):
event.setAccepted(True)
def mouseMoveEvent(self, event: QGraphicsSceneMouseEvent):
if event.buttons() & Qt.LeftButton:
self.setPos(self.mapToParent(event.pos() - event.buttonDownPos(Qt.LeftButton)))
event.setAccepted(True)
else:
event.setAccepted(False)
class View(QGraphicsView):
def __init__(self, parent=None):
super().__init__(parent)
self.m_callouts: List[Callout] = []
self.setDragMode(QGraphicsView.NoDrag)
self.setVerticalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
self.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
# chart
self.m_chart = QChart(parent)
self.m_chart.setMinimumSize(640, 480)
self.m_chart.setTitle("Hover the line to show callout. Click the line to make it stay")
self.m_chart.legend().hide()
series = QLineSeries()
series.append(1, 3)
series.append(4, 5)
series.append(5, 4.5)
series.append(7, 1)
series.append(11, 2)
self.m_chart.addSeries(series)
series2 = QSplineSeries()
series2.append(1.6, 1.4)
series2.append(2.4, 3.5)
series2.append(3.7, 2.5)
series2.append(7, 4)
series2.append(10, 2)
self.m_chart.addSeries(series2)
self.m_chart.createDefaultAxes()
self.m_chart.setAcceptHoverEvents(True)
self.setRenderHint(QPainter.Antialiasing)
self.setScene(QGraphicsScene())
self.scene().addItem(self.m_chart)
self.m_coordX = QGraphicsSimpleTextItem(self.m_chart)
self.m_coordX.setPos(self.m_chart.size().width() / 2 - 50, self.m_chart.size().height() - 20)
self.m_coordX.setText("X: ")
self.m_coordY = QGraphicsSimpleTextItem(self.m_chart)
self.m_coordY.setPos(self.m_chart.size().width() / 2 + 50, self.m_chart.size().height() - 20)
self.m_coordY.setText("Y: ")
self.m_tooltip = Callout(self.m_chart)
self.scene().addItem(self.m_tooltip)
series.clicked.connect(self.keep_callout)
series.hovered.connect(self.tooltip)
series2.clicked.connect(self.keep_callout)
series2.hovered.connect(self.tooltip)
self.setMouseTracking(True)
def resizeEvent(self, event: QResizeEvent):
if scene := self.scene():
scene.setSceneRect(QRectF(QPointF(0, 0), QSizeF(event.size())))
self.m_chart.resize(QSizeF(event.size()))
self.m_coordX.setPos(self.m_chart.size().width() / 2 - 50, self.m_chart.size().height() - 20)
self.m_coordY.setPos(self.m_chart.size().width() / 2 + 50, self.m_chart.size().height() - 20)
for callout in self.m_callouts:
callout.updateGeometry()
super().resizeEvent(event)
def mouseMoveEvent(self, event: QMouseEvent):
from_chart = self.m_chart.mapToValue(event.pos())
self.m_coordX.setText(f"X: {from_chart.x()}")
self.m_coordX.setText(f"Y: {from_chart.y()}")
super().mouseMoveEvent(event)
def keep_callout(self):
self.m_callouts.append(self.m_tooltip)
self.m_tooltip = Callout(self.m_chart)
self.scene().addItem(self.m_tooltip)
def tooltip(self, point: QPointF, state: bool):
if not self.m_tooltip:
self.m_tooltip = Callout(self.m_chart)
if state:
self.m_tooltip.setText(f"X: {point.x()} \nY: {point.x()} ")
self.m_tooltip.m_anchor = point
self.m_tooltip.setZValue(11)
self.m_tooltip.updateGeometry()
self.m_tooltip.show()
else:
self.m_tooltip.hide()
if __name__ == '__main__':
app = QApplication(sys.argv)
window = View()
window.resize(640, 480)
window.show()
sys.exit(app.exec_())